diff options
| author | Nicholas Piggin | 2021-04-29 22:58:49 -0700 |
|---|---|---|
| committer | Linus Torvalds | 2021-04-30 11:20:40 -0700 |
| commit | 121e6f3258fe393e22c36f61a319be8a4f2c05ae (patch) | |
| tree | 0e4b1115e5964be35140a54e60d625f6a25d26c6 /include | |
| parent | 5d87510de15f31d1b26cffced7bc4d504539a2c7 (diff) | |
mm/vmalloc: hugepage vmalloc mappings
Support huge page vmalloc mappings. Config option HAVE_ARCH_HUGE_VMALLOC
enables support on architectures that define HAVE_ARCH_HUGE_VMAP and
supports PMD sized vmap mappings.
vmalloc will attempt to allocate PMD-sized pages if allocating PMD size or
larger, and fall back to small pages if that was unsuccessful.
Architectures must ensure that any arch specific vmalloc allocations that
require PAGE_SIZE mappings (e.g., module allocations vs strict module rwx)
use the VM_NOHUGE flag to inhibit larger mappings.
This can result in more internal fragmentation and memory overhead for a
given allocation, an option nohugevmalloc is added to disable at boot.
[colin.king@canonical.com: fix read of uninitialized pointer area]
Link: https://lkml.kernel.org/r/20210318155955.18220-1-colin.king@canonical.com
Link: https://lkml.kernel.org/r/20210317062402.533919-14-npiggin@gmail.com
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ding Tianhong <dingtianhong@huawei.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/vmalloc.h | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h index ae9eb07d30d4..b4c82f2d40dc 100644 --- a/include/linux/vmalloc.h +++ b/include/linux/vmalloc.h @@ -26,6 +26,7 @@ struct notifier_block; /* in notifier.h */ #define VM_KASAN 0x00000080 /* has allocated kasan shadow memory */ #define VM_FLUSH_RESET_PERMS 0x00000100 /* reset direct map and flush TLB on unmap, can't be freed in atomic context */ #define VM_MAP_PUT_PAGES 0x00000200 /* put pages and free array in vfree */ +#define VM_NO_HUGE_VMAP 0x00000400 /* force PAGE_SIZE pte mapping */ /* * VM_KASAN is used slighly differently depending on CONFIG_KASAN_VMALLOC. @@ -54,6 +55,9 @@ struct vm_struct { unsigned long size; unsigned long flags; struct page **pages; +#ifdef CONFIG_HAVE_ARCH_HUGE_VMALLOC + unsigned int page_order; +#endif unsigned int nr_pages; phys_addr_t phys_addr; const void *caller; @@ -188,6 +192,22 @@ void free_vm_area(struct vm_struct *area); extern struct vm_struct *remove_vm_area(const void *addr); extern struct vm_struct *find_vm_area(const void *addr); +static inline bool is_vm_area_hugepages(const void *addr) +{ + /* + * This may not 100% tell if the area is mapped with > PAGE_SIZE + * page table entries, if for some reason the architecture indicates + * larger sizes are available but decides not to use them, nothing + * prevents that. This only indicates the size of the physical page + * allocated in the vmalloc layer. + */ +#ifdef CONFIG_HAVE_ARCH_HUGE_VMALLOC + return find_vm_area(addr)->page_order > 0; +#else + return false; +#endif +} + #ifdef CONFIG_MMU int vmap_range(unsigned long addr, unsigned long end, phys_addr_t phys_addr, pgprot_t prot, @@ -205,6 +225,7 @@ static inline void set_vm_flush_reset_perms(void *addr) if (vm) vm->flags |= VM_FLUSH_RESET_PERMS; } + #else static inline int map_kernel_range_noflush(unsigned long start, unsigned long size, |